NERVOUS SYSTEM Sydney Hirrschoff

NERVOUS SYSTEM FUNCTION The nervous system is made up of the brain, spinal cord, sensory organs, and all of the nerves that connect these organs with the rest of the body. Together, these organs control the body and are responsible for the communication among it’s parts.

http://discoverykids.com/articles/your-nervous-system/

CENTRAL NERVOUS SYSTEM Central nervous system Made up of brain and spinal cord “Control center” of the body Responsible for memory, processing, and regulation systems Uses sensory information to control the body and maintain homeostasis Determines other functions that make up our personality and who we are

https://www.healthtap.com/topics/vitamins-to-improve-central-nervous-system-function

PERIPHERAL NERVOUS SYSTEM Consists of the nerves and ganglia outside of the brain and spinal cord

Has 2 types of cells1. sensory nervous cells- carries information to the central nervous system 2. motor nervous cells- carries information from the central nervous system

https://askabiologist.asu.edu/parts-nervous-system

INTERACTION OF TWO NEURONS

SIMPLE REFLEX ARC

SIMPLE REFLEX ARC ELEMENTS A reflex arc defines the pathway by which a reflex travels, from the stimulus to sensory neuron to motor neuron to reflex muscle movement

Elements Receptor- triggers if stimulus is great enough to generate Sensory neuron-converts external stimuli that comes from the environment into corresponding internal stimuli

Motor neuron- directly or indirectly controls muscles Effector- what is effected by the stimuli

Example of simple reflex arc in action: pulling your hand away from a hot stove

BRAIN PARTS DRAWING

FUNCTIONS OF MAJOR BRAIN PARTS Right hemisphere- controls left half of body, nonverbal skills, special perception

Left hemisphere- controls right half of body, language,

Diencephalon- contains the thalamus and hypothalamus, thus making it an important relay station for sensory information

Brian stem- connects brain to spinal cord and passes messages between them through the medulla

Cerebellum- controls balance and muscular coordination

HOW NERVE IMPULSES TRAVEL

Signals are transmitted from neuron to neuron via an action potential, when the axon membrane rapidly depolarizes and repolarizes.

https://www.boundless.com/biology

KEY CONCEPTS OF HOW NERVE IMPULSES TRAVEL Membrane potential-the difference in electrical polarization or charge between two sides of a membrane or cell wall

Resting potential- position where the neuron is inactive and polarized

Na⁺- outside of the cell contains excess sodium ions

K⁺- inside the of the cell contains excess potassium ions

Action potential-a short term change in the electrical potential that

travels along a cell

Depolarization-a decrease in the difference in voltage between the inside and outside of the neuron

Threshold- point in which a stimulus triggers a nerve impulse

Refractory period- period where everything is put back to normal

ROLE OF NEUROTRANSMITTERS Neurotransmitters are the chemicals in the brain that carry information to the whole body

Neurotransmitters tell the heart to beat, stomach to digest, lungs to breathe

Also controls emotions and feelings

Transmit signals from a neuron across a synapse to a target cell.

IPSP- inhibitory Calm the brain and help create balance Control mood

EPSP- excitatory Stimulate the brain Overpower IPSP

http://www.cbsnews.com/news/smart-parents-smart-kids/

ALZHEIMER’S DISEASE

Progressive, neurodegenerative disease that occurs when nerve cells in the brain die

Symptoms and signs: memory loss, confusion, change in personality, language deterioration, restlessness, disorientation of time and place, misplacing things

Today it is considered the most common cause of dementia

Over 5.3 million Americans have Alzheimer’s and most of those suffering are over 65

There are no known treatments yet, but physical and mental exercise can help slow the symptoms

Progressive so will eventually lead to death

PARKINSON’S DISEASE

Slowly progressing degenerative disease that results in the loss of dopamine-producing brain cells

medical experts believe the symptoms are related to a chemical imbalance in the brain caused by brain-cell death

Symptoms: trembling of body parts and face, postural instability, impaired balance and stability, stiffness of bones and joints, muscle rigidity

About 60,000 Americans diagnosed per year and over 1 million will have Parkinson’s at any one time

As of today there is no cure all for Parkinson’s Disease. Medicatons, surgery, exercise, physical therapy, and speech therapy may help with symptoms

Chronic and progressive so will eventually lead to death

REFERENCE PAGE

http://www.innerbody.com/image/nervov.html

http://biology.about.com/od/organsystems/a/aa061804a.htm

https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/the-peripheral-nervous-system-pns-13/reflexes-136/components-of-a-reflex-arc-727-2295/

http://www.cerebromente.org.br/n01/arquitet/hemisferios_i.htm

http://psychology.jrank.org/pages/92/Brain.html

https://www.boundless.com/biology/textbooks/boundless-biology-textbook/the-nervous-system-35/how-neurons-communicate-200/nerve-impulse-transmission-within-a-neuron-action-potential-762-11995/

http://www.dummies.com/how-to/content/understanding-the-transmission-of-nerve-impulses.html

http://medical-dictionary.thefreedictionary.com/membrane+potential

https://www.neurogistics.com/TheScience/WhatareNeurotransmi09CE.asp

http://uhealthsystem.com/health-library/neuro/disorder